1. Field of the Invention
This invention relates to a battery pack connection, and more particularly, a battery pack connection in which a battery pack can be quickly and efficiently replaced upon discharge of the batteries.
2. Description of Prior Art
The present invention has particular utility when used with electrical devices that are portable and which derive their power from batteries that are contained within a pack and which are generally connected by a cable to the device. Typically, the power supplied by the battery pack is utilized quite rapidly requiring frequent replacement of a discharged battery pack by a freshly charged pack. Heretofore, the replacement of a pack has generally required both an operation which effects disconnecting of the electrical connection between the pack and the device and also another operation which separates the pack from its supporting structure so that not only was replacement somewhat timeconsuming and requiring the user's undivided attention, but also it was susceptible to improper securement and connection.
Therefore, in U.S. Pat. No. 4,218,107, assigned to the same assignee as the present invention, a battery pack connection is disclosed which includes a female plate that is secured, as for example, directly to a portable device or may be carried by the user by being strapped to the user's body. The female plate is formed with a plurality of keyholes together with at least one male terminal with the keyholes and the terminal extending in the same direction but with the terminal being positioned within a recess spaced beneath the plane of the female plate. A male plate cooperates with the female plate and may form one side of a battery containing recepticle or pack. The male plate has a plurality of circular headed projections extending therefrom and at least one female terminal positioned within a housing that projects from the plane of the male plate.
In use, the female plate is fixed and connected to the electrical device and if the male plate is part of the battery pack, the user positions the male plate against the female plate with initial alignment occurring between the recess and the housing and with said alignment preventing lateral shifting of the plate with respect to the slots of the keyholes. The user can then only move the male plate in the direction of the keyhole slots until the headed projections enter into circular openings of the keyholes. The male plate is then further moved to position the projections within the slots of the keyholes with said movement causing electrical connection between the male and female terminals.
When the male plate has achieved its connected position, a tensioned flexible strip that is positioned behind one keyhole reverts to its normally biased position wherein it has a ledge which engages the head of the projection in said keyhole and prevents the two plates from moving from their connected position.
For removing the plate, the user merely bends the flexible strip from its normal position which unlocks the engagement between the strip and the projection to thereby permit the male plate to be moved so as to position the headed projections within the circular openings of the keyholes. At this position, the terminals have been disconnected and the male plate can be removed from the female plate in order to permit a charged battery pack to be replaced on the female plate.
The portion of the keyholes in the female plate for receiving the circular headed projections on the male plate are also all circular in shape and of a similar diameter. This precise horizontal and vertical alignment of all the projections simultaneously with the respective keyholes is a prerequisite for proper engagement of the two parts. This prealignment process is relatively difficult and has the undesirable effect of impeding the overall speed of engagement. This design also requires two distinct and perpendicular motions for full engagement; insertion of the projections into the keyholes followed by a lateral motion which make electrical contact and locks the mating parts. This double motion further reduces the overall speed of engagement. Also, in order to remove the male plate from the female plate so as to readily replace the battery pack, it was necessary to hold the flexible strip in its bent position with one hand while removing the male plate with the other, which is somewhat awkward. In addition to requiring two hands, disengagement was further complicated by the requirement of two distinct motions; a lateral movement to electrically disconnect followed by a retraction in a direction perpendicular to the first. The improved structure of this invention cures these problems.